An assembled battery including a plurality of cells connected through a bus bar is known as a battery having a higher capacity and a higher output as compared with a battery for a portable device such as for an electrically powered tool driving power source and for a vehicle driving power source. The bus bar is fixed by fastening a nut to a terminal electrode protruding from the cell. Patent Document 1 has disclosed a battery having a lid plate having a terminal lead-out through hole bored therein and having a rotation preventing portion formed on an upper face to protrude upward, a take-out electrode having a lower portion inserted into a battery container through the terminal lead-out through hole and connected to metal foil of a power-generating element, the take-out electrode being sealed and secured to the lid plate through an insulating sealing agent, a connecting electrode connected and fixed to an upper portion of the take-out electrode, and an external terminal having a bolt portion formed to protrude from a seat portion and passed through a terminal inserting hole in the connecting electrode from below, the seat portion being locked on the rotation preventing portion of the lid plate to limit the rotation of the bolt portion about its axis.